1. Field of the Invention
The invention relates generally to apparatus and methods for generating three dimensional surface models of moving objects, and more particularly to using multiple devices simultaneously to generate three dimensional surface models.
2. Background of the Invention
The generation of three dimensional models of moving objects has uses in a wide variety of areas, including motion pictures, computer graphics, video game production, human movement analysis, orthotics, prosthetics, surgical planning, sports medicine, sports performance, product design, surgical planning, surgical evaluation, military training, and ergonomic research.
Two existing technologies are currently used to generate these moving 3D models. Motion capture techniques are used to determine the motion of the object, using retro-reflective markers such as those produced by Motion Analysis Corporation, Vicon Ltd., active markers such as those produced by Charnwood Dynamics, magnetic field detectors such as those produced by Ascension Technologies, direct measurement such as that provided by MetaMotion, or the tracking of individual features such as that performed by Peak Performance, SIMI. While these various technologies are able to capture motion, nevertheless these technologies do not produce a full surface model of the moving object, rather, they track a number of distinct features that represent a few points on the surface of the object.
To supplement the data generated by these motion capture technologies, a 3D surface model of the static object can be generated. For these static objects, a number of technologies can be used for the generation of full surface models: laser scanning such as that accomplished by CyberScan, light scanning such as that provided by Inspeck, direct measurement such as that accomplished by Direct Dimensions, and structured light such as that provided by Eyetronics or Vitronic.
While it may be possible to use existing technologies in combination, only a static model of the surface of the object is captured. A motion capture system must then be used to determine the dynamic motion of a few features on the object. The motion of the few feature points can be used to extrapolate the motion of the entire object. In graphic applications, such as motion pictures or video game production applications, it is possible to mathematically transform the static surface model of the object from a body centered coordinate system to a global or world coordinate system using the data acquired from the motion capture system.
To enhance a system that produces a model of the surface of a three dimensional object, with the object possibly in motion and the object possibly deforming in a non-rigid manner, there exists a need for a method for operating multiple devices simultaneously. One problem to address relates to potential interference between multiple devices in operation: an imaging device that projects a pattern onto one aspect of an object and then observes that pattern with the goal of estimating the three dimensional surface may be thwarted if a second device is also projecting a pattern onto that surface. In order to successfully operate multiple devices on one object, the present invention disclosed a novel method for operating multiple devices without interference.